Chapter 15: Now having finished the discussion of his "protectors," Frankenstein's monster describes three books that he finds near the cottage and decides to read. Usually, he explains, these books (Paradise Lost, Plutarch's Lives, and Sorrows of Werter) only serve to make him sink "into the lowest dejection." He is especially struck by what he reads about Adam in Paradise Lost. Though he identifies with Adam in that he's the first of his kind, the monster isn't in contact with his creator the way Adam is, and is "wretched, helpless and alone." He also discovers in his pocket, Frankenstein's notes to himself during the time of his creation; reading this only further disgusts him.
Finally, the monster builds up his courage enough to make contact with the cottagers. He waits until everyone but the old man has left to go on a walk. Then he advances towards the cabin, knowing that the blind, old man will not see him and won't be thunderstruck by his horrific appearance. He enters the house and makes pleasant conversation with the old man, who receives him warmly enough. But just when he's about to reveal his identity, Felix, Agatha and Safie walk in, back from their walk. They take one look at the beast and are immediately frightened to death. Felix hits the monster with a stick, and the beast hurriedly retreats to his hovel.
Chapter 16: Chapter 16 marks a stark change in the monster's attitude toward men. No longer does he try to mold himself into human society; instead, he decides to take out his anger on mankind. He explains, "There was non among the myriads of men that existed who would pity or assist me; and should I feel kindness towards my enemies? No: from that moment I declared everlasting war against the species, and, more than all, against him who had formed me and sent me forth to this insupportable misery."
When he returns to the cottage, having resolved to try his luck once more with the human species, he discovers that they have left for good. Overhearing Felix speaking to some local men, he learns the trauma of the previous day has proven too much for the whole De Lacey family. Thus, the beast feels betrayed by the family he has grown to love, and he continues to develop a deep-ceded hatred for mankind.
Traveling alone, the monster sees a girl fall into a river. Saving her from drowning, he drags her up, out of the current, setting her on dry ground. When the man who had been with her sees the child in his arms, he quickly snatches her away, fleeing the scene. When the monster follows the pair, the man fires a gun at the beast, striking him in the shoulder. Once again the beast curses mankind, promising to avenge the cruelty he has suffered.
Several weeks later, now near Geneva, the monster encounters a small boy walking through the forest. Hoping to show the young boy that's he's not so hideous after all, the beast picks up the child, who begins to scream. When the boy (who is William Frankenstein) tells the monster that his dad is M. Frankenstein, the beast immediately identifies him with his enemy and creator, and strangles the child. Later that night, he encounters a young woman (Justine) sleeping on a pile of straw. In order to place the blame of the murder onto her, he puts the portrait that William had been carrying into her pocket.
At the end of his speech, the monster relates his desire for Frankenstein to create a special being of his species "as deformed and horrible" as himself.